Frances Andrade, a talented violinist, took her own life after being called a liar and a fantasist in court by the barrister defending Michael Brewer, the choirmaster who was later convicted of abusing her when she was a teenage music student.

Mrs Andrade’s family told how one of the key failings by the criminal justice system had been a warning by police that she should not seek counselling to cope with the trauma of going to court, a decision which they felt was particularly damaging because of her history of self-harm.

Last night Greater Manchester Police, which investigated the crimes committed against Mrs Andrade, sought to distance itself from the decision.

It blamed Surrey Police, the victim’s local force, for giving what her family described as “heavy advice” not to seek psychological help during the two years running up to the trial.

The Surrey force declined to comment. The accusation comes less than a month after it was heavily criticised for bungling the investigation it ran between 2007 and 2009 into Jimmy Savile, the entertainer who was later named as a serial paedophile.

Pressure is mounting for an investigation “from start to finish” into how Mrs Andrade’s case was handled by police, the Crown Prosecution Service and the courts.

Mrs Andrade, a mother of four, did not make the original complaint to the police. The investigation was triggered when a friend, in whom she had confided, reported Mr Brewer and his former wife Kay, both 68, to the police.

Last week, following a trial at Manchester Crown Court, the Brewers were convicted of sexually abusing Mrs Andrade 30 years ago, when she was a pupil at the city’s renowned music school Chetham’s, where Mr Brewer once taught.

The jury was not told that Mrs Andrade, 48, the principal witness against the Brewers, died from an overdose six days after giving evidence.

She had become visibly agitated by the defence barrister’s attempts to discredit her. At one point as she was cross-examined, she said: “This feels like rape all over again.”

The victim’s family, from Guildford, Surrey, said she had been reluctant to give evidence but had felt pressurised by the police.

They also criticised the CPS for failing to support her properly in the run-up to the trial, and disclosed a catalogue of mistakes and omissions in the way the vulnerable witness had been treated by the criminal justice system.

In a moving statement issued after the trial, Mrs Andrade’s son, Oliver, said she had been “left in the dark” about the case, and only met the prosecutor, Peter Cadwallader, for a “scant 10 minutes” before appearing in the witness box.

To cap it all, it emerged after Mrs Andrade’s death that on police advice she had struggled alone with the psychological trauma of resurrecting memories of the abuse in her teenage years.

“Having been heavily advised by the police not to receive any form of therapy until the end of the case, she was forced to cope on her own with only the support of her family and very close friends,” said Oliver, 21.

It also emerged that Mrs Andrade had previously attempted suicide several times, and that between the ages of eight and 16 she had been repeatedly raped by an uncle.

The CPS said it had not advised against therapy.

A spokesman for Greater Manchester Police (GMP) added: “It was Surrey Police that told Mrs Andrade not to seek help. At no point was she told by GMP not to seek therapy.

“That would have breached our policies on this type of situation.”

Det Chief Supt Mary Doyle, from GMP, added: “The advice to Frances not to seek support may have been given by another party but it was not the advice of Greater Manchester Police. Victims who have suffered sexual abuse have every right to seek whatever help they need.”

Surrey Police declined to comment on the allegation made by the other police force. A spokesman said only: “It is Surrey Police’s policy to encourage victims to seek appropriate support.

“The death of Frances Andrade is extremely saddening and, as one of a number of agencies who had contact with her, we will review our involvement in her case.”

Criminal justice experts last night expressed their concern at the lack of support Mrs Andrade received from the police and the CPS.

Sir Paul Stephenson, the former Metropolitan Police commissioner, predicted that there would be an inquiry into the handling of the case. “It’s very easy for people like me to criticise after leaving office, but I am sure there will be a review of the processes and the decisions that have been made,” he said.

“I’m sure the people involved will want to review it and reflect upon whether it could have been handled better.

“The criminal justice system should not always be easy and it can, regrettably, sometimes be very punishing on the victim. But it is truly shocking that a victim of crime could have been driven to harm themselves in this way.”

Jo Wood, a trustee of Rape Crisis, said: “Frances Andrade could have had the support she needed and we feel absolute despair that she did not receive it. But she was just thrown to the wolves.

“She was just treated, it seems, as if she was a piece of evidence or a crime scene, and nothing else.

“Surrey Police could do with some training, to put it mildly. This highlights how the treatment you will receive really is a postcode lottery, with victim care varying very much on where you live.”

Geoffrey Bindman, the leading criminal QC, said: “I find it really remarkable that the police advised her not to seek medical advice that one obviously needs in a situation like that.

“I have never come across it before and it’s very difficult to understand why they would have done it.”

Fran Swaine, a managing partner at Leigh Day solicitors, who has worked on historic sexual abuse cases for 20 years, said: “I understand this lady did not receive appropriate support from the CPS, and that would not surprise me in the least based on the experience of clients of mine in the past.

“She apparently did not meet the prosecuting barrister until shortly before taking the witness stand, and that is something that has happened to my clients. The CPS are quite often uncoordinated and not properly resourced to deal with victims in the way they should.”

Yvette Cooper, the shadow home secretary, said: “There must be an urgent investigation into the handling of this case from start to finish. Although the details are still emerging, it looks as though something went badly wrong.”

The CPS refused to disclose which prosecutor took the decision to proceed with the case, saying only that the Chief Crown Prosecutor for the North West, Nazir Afzal, took responsibility for all CPS decisions in the area.